Pacific Flyway Waterfowl Show Signs of Comeback : Environment: The Central Valley sees a rising number of migratory birds. Human efforts and nature share credit.

It is loafing time in the vast Central Valley, and about 2,000 birds are spending the twilight hours lounging at Swan Lake, a glassy pearl of fresh water and wispy cattails that was bone dry two winters ago.

Ducks dabble and quack, their afternoon overture joined by a choir of squawking gulls and honking geese. Amid the din, elegant white pelicans preen silently on the pond’s sand island, and a chorus of blackbirds spirals upward, their hundreds of wings a dark cloud that blots out the sun before the birds glide back to earth.

After two decades of a disquieting hush at North America’s marshes and prairies, the sights and sounds of Swan Lake are a symphony of renewal.

Since the mid-1970s, biologists have worried about vanishing waterfowl, warning that the flocks of wild ducks and other birds that had seemed an indelible part of the continent’s landscape were dwindling. The decline in migratory birds, mainly the result of persistent drought and filling of fresh-water wetlands, has long posed one of North America’s most insidious ecological problems.

Now, for the first time, Western waterfowl are making a comeback. Populations of ducks and other birds have begun to slowly rebound in the Pacific Flyway, the broad band of Western sky from the Arctic Ocean to Mexico traversed by 20% of North America’s migratory birds, according to research by the U.S. and Canadian governments.

Cautiously optimistic waterfowl experts give half the credit--as they did half the blame--to Mother Nature and half to human influences. A decade-long drought in key nesting areas of western Canada ended last year and a multimillion-dollar effort was launched in the mid-1980s to rebuild North American marshes where the birds breed and feed, such as Swan Lake.

“In just one season, as remarkable as it may sound, the birds seem to have responded. That’s the impression everyone has,” said Chris Unkle, California wetlands director at the Nature Conservancy, an international conservation group. “We’ve definitely turned the tide. We’re going to see some dramatic improvements in the overall health of the flyway in the next 10 years.”

The most encouraging signs emerged in January, when a mid-winter survey showed that populations of ducks, geese and swans in the Pacific Flyway were 5% higher than their average for the previous 10 years, according to the U.S. Fish and Wildlife Service. In California, about 380,000 more ducks, geese, swans and coots--an 11% increase--were reported.

While 5% is only a slight gain, the 1994 bird counts signaled a turnaround that confirms the hunches of biologists and refuge managers like Gary Zahm, who oversees California’s largest remaining complex of freshwater wetlands. “I think,” said Zahm as he watched flocks of ducks feeding in the sprawling San Luis National Wildlife Refuge, “that we are poised on a major recovery this spring.”

Fifteen hundred miles away, the optimism is echoed by a Canadian counterpart, government biologist Bruce Turner, who enthusiastically recites last summer’s numbers of breeding ducks in southern Alberta--pintails up 258%, shovelers 75%, wigeons 17%. Even better, he says, this year’s nesting sites “are the best I’ve seen for a long time.”

The promising bird counts come eight years and $138 million after a large public and private wetlands revival began in California, and five years after former President Bush pledged to Ducks Unlimited that “recovery, restoration and renewal” of the resource is “our moral imperative.”

Nevertheless, everyone agrees that a recovery is slow and precarious, and although some of the patient’s vital signs are improving, waterfowl experts warn against prematurely shutting off the life support--the money and water to restore wetlands.

“It’s too early to tell if we are on our way back,” cautioned Lew Oring, director of ecology and conservation biology at the University of Nevada at Reno. “As far as the ducks are concerned, it is a very long and complicated road and at best we will have some species that recover and some that will never recover.”

Even under the best conditions, North America’s ducks and other species probably will never again reach the healthy numbers of the 1970s because so many of their breeding and wintering sites have been drained or developed. Federal and state biologists counted 5.6 million ducks, geese and swans in the Pacific Flyway in January, substantially better than the record low of 4.3 million in 1989, but still 19% below their long-term average of 7 million birds from 1955 through 1992.

Skeptics also point out that while the Far Western flyway is faring better, the rest of the continent is not. “A miraculous recovery has not occurred,” warned George Hochbaum, a Canadian Wildlife Service biologist in Manitoba.

In fact, duck hatching at key locations in central Canada and the Midwestern United States declined again last summer, a disappointment that leaves longtime Manitoba nature photographer Jack Barrie tempted to pack away his cameras in disgust. “In some areas,” he said, “it isn’t even worth going out anymore to take pictures.”

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Just after the turn of the century, ornithologist Frank Chapman visited Los Banos, describing the heart of California as “green marshes and shining ponds . . . fairly twinkling with flitting wings.”

“I have never,” he exulted in 1908, “seen birds more abundant.”

Back then, perhaps 60 million birds migrated to California’s wetlands each winter, knitting a feathery blanket in the sky that captured the imaginations of poets and photographers, authors and artists.

Today, the Central Valley evokes few lyrical responses. Its skies are much emptier, attracting about 2.5 million birds each winter, and most of its “green marshes and shining ponds” long ago were converted to crops and aqueducts.

When allowed to flow naturally, runoff of the Sierra Nevada emptied into a giant trough that is the Central Valley, and spun a web of rivers and marshes that provided shelter and food for waterfowl.

Today, not a single bend or crook of the rivers remains natural; every movement is commanded by dams and channels that funnel irrigation water to rural crops and city faucets. About 95% of California’s original 4 million acres of wetlands have been drained and now sustain the lives of 30 million people instead of 60 million birds.

“You really don’t have a wetland in California unless someone writes a check and opens up a floodgate and gets the water delivered,” said Brad Bortner, migratory bird specialist with the U.S. Fish and Wildlife Service’s western regional office in Portland, Ore.

Waterfowl felt the strain of the water diversions. Declines in North American wild duck populations started in the late 1970s and early ‘80s. Especially hard hit were pintails, a duck with zigzagging flock patterns once plentiful in California; its population has plummeted by two-thirds.

Biologists say that ensuring Central Valley wetlands are in good shape is of international importance because 60% of the Pacific Flyway’s birds winter there. If the wintering grounds are in poor condition, birds cannot find enough protein and fat to survive the journey home.

But California alone did not cause the decline. The dry condition of the Canadian prairies, where many Pacific Flyway birds are born each summer, played a major role.

“That local population of birds there in California is really doing well,” said Hochbaum. “But what happens in the hinterlands tells the story of how those populations will respond over time, whether they will go up or whether they will go down.”

For 10 years, most of the breeding grounds in the prairie potholes of Canada and the northern United States were parched from a record-long drought. At the same time, grain prices skyrocketed, giving landowners an economic incentive to rapidly convert the dry land into wheat fields.

When grain prices stabilized and the drought ended, the scene started to change.

“Last summer, there were ponds everywhere, in places where there had never been water before,” said Turner, who specializes in Pacific Flyway populations for the Canadian Wildlife Service.

Many of the birds responded immediately. In southern Alberta, the number of breeding pintails reported in 1993 was almost triple that of the previous year, according to the Canadian Wildlife Service.

This spring looks equally promising, Turner said, since winter storms dropped plentiful snow on western Canada. Birds probably will find plenty of spring ponds when they return north to breed, he said.

“Now all we need,” Turner said, “is all these birds coming back (from California) in good shape.”

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For years, Swan Lake was a misnomer.

A rancher who owned the land had turned more than 5,000 acres of marsh, including the small pond, into a barren flat by diverting water so his cattle could graze. Ultimately, he went bankrupt, and in 1992, he sold the property for $1,000 an acre to the U.S. government, which restored Swan Lake’s natural state by letting the water flow back in.

Gary Zahm would not have believed the transformation if he had not witnessed it himself. Within a month, hundreds of waterfowl began feeding and resting at the new pond. Within a year, cattails, a major source of shelter and food for birds, reappeared.

“When the birds fly over it and see it, this is like paradise to them,” said Zahm, the U.S. Fish and Wildlife Service’s project leader at the San Luis refuge complex in Los Banos. “It’s like their ancestors used to see the whole valley.”

To rebuild the pond, the federal agency provided little more than a bulldozer that created a new inlet and a supply of fresh water diverted from Shasta Lake.

“You can almost add water and get instant bird use,” Zahm said. “The Central Valley has lost so many of its wetlands that if you produce them anywhere near the area, the birds react to it right away.”

Tiny Swan Lake is just one example of the thousands of acres of wetlands rebuilt since the mid-1980s in the Central Valley, the region identified by the U.S. government as its top priority for restoring wetlands.

Since 1986, federal and state governments, environmentalists and duck hunting clubs in an ambitious project called the Central Valley Habitat Joint Venture have spent $138 million to create, improve and preserve wetlands. So far, they have restored water to 27,000 acres of dried up land, enhanced 100,000 acres of existing wetlands and purchased another 107,000 acres of wetlands from farmers and other private property owners.

“Cumulatively,” Oring said, “these wetlands restorations and the curtailment of additional losses is bound to keep a whole host of wetlands species from going extinct or having serious population crashes.”

Resurrection of the flyway means scrounging not just for money but for water--California’s most precious commodity. In that regard, helping waterfowl has not been painless for California’s farmers.

Adopted by Congress two years ago, the Central Valley Project Improvement Act diverted large amounts of water from crops and provided it to wildlife and fish. Under the act, Central Valley wetlands were allocated three times more federally managed water last year than in 1992, and the amount will increase 10% every year for the next decade.

“If we have the water to do it, it’s not that much of an issue. But given our (water) deficit situation in California, particularly the longterm projections, farmers are very concerned,” said Mary-Ann Warmerdam, the California Farm Bureau’s director of natural resources.

In California, the first hint that restoration dollars and more plentiful water have helped came in August, when refuge managers noticed that more pintails and green-winged teals were arriving from Canada.

In addition to the ducks, other migratory waterfowl seem to be doing much better, especially sandhill cranes, which at three feet tall are one of North America’s largest birds.

“It has been phenomenal,” said Charlie Stenvall, manager of the Merced National Wildlife Refuge. “I see it on a day-to-day basis and there is no comparison. Normally we would expect to see 3,000 cranes foraging on the refuge. But this year we had 9,000 or 10,000.”

Such reports, however, can be deceiving, since resuscitating an injured population takes many years. A decade of successful breeding seasons probably will have to pass before biologists will feel confident enough to declare the crisis over.

“I am speaking optimistically and prematurely when I say we are seeing a recovery,” said Glenn Olson, western regional representative of the National Audubon Society. “I hope it’s not just wishful thinking.”

Even hunters--who like to cast a positive spin on the government’s bird counts because their shooting limits have dropped from 35 ducks allowed per day in the 1950s to four last year--warn that the crisis is not over.

“Things are looking up,” said Bob McLandress, research biologist with the California Waterfowl Assn., an organization mainly of duck hunting clubs. “But unfortunately, we are still at the whim of nature.”

Waterfowl biologists, who have tried to unravel mysterious fluctuations in migratory bird populations for years, warn that throwing money and water at the problem is not the whole cure.

Understanding the complexities of nursing the Pacific Flyway back to good health takes a bird’s-eye view:

In summer, a Pacific Flyway duck is born in the freshwater ponds of Alberta, the Yukon or Alaska. Then, every fall, it heeds its mysterious internal voice and flies about 2,000 miles south to warmer climes in California and Mexico. In March, it wings back home, repeating the treacherous flight in the opposite direction.

Along the way, each bird encounters any number of man-made and natural dangers, from quirky weather in the Arctic to deadly selenium poisoning in California. For its species to flourish, it has to do more than survive the trek--it must arrive fit and fat enough to breed.

“There is no miracle cure,” said Hochbaum, who is experimenting in Manitoba with creating the right breeding conditions for waterfowl. “We’ve created all kinds of ponds up here, and we now have more ponds than ducks. But water doesn’t make ducks, and dollars don’t make ducks. Only ducks make ducks.”

A Bird’s-Eye View

The Pacific Flyway is the vast corridor of sky across western North America that stretches from the Arctic Ocean to Mexico. About 20% of the continent’s migratory birds use this path for their annual flight, breeding in the northern prairies every summer, flying south every fall and returning every spring. The ponds and lakes of California’s Central Valley are their most popular winter retreat, attracting 60% of the flyway’s ducks, geese and other waterfowl.

Pacific Flyway

CANADA

1. Alaska

2. Washington

3. Oregon

4. California

5. Arizona

6. New Mexico

7. Colorado

8. Utah

9. Wyoming

10. Montana

11. Idaho

12. Nevada

Improving Populations

Migratory waterfowl in the Pacific Flyway have reached their most encouraging numbers in years, according to an annual mid-winter survey conducted last month. Most species, however, still have a long way to go to reach the healthy populations of decades ago. Every January, migratory birds--mostly ducks, geese, swans and coots--are counted by federal and state biologists in aircraft and on the ground.

1955-1992 1994 1992 1985 Average Ducks 4,409,697 4,320,985 3,944,667 5,994,168 Geese 1,157,281 1,103,786 714,666 896,562 Swans 83,201 65,856 49,730 54,416 Coots 435,789 310,103 161,996 495,687

Source: U.S. Fish and Wildlife Service, mid-winter surveys of Pacific Flyway